One embodiment the invention relates to a process for the control of the voltage supply of a semiconductor component, as well as a voltage supply control device.
In semiconductor components, for instance computing circuits, for instance micro-controllers or micro-processors and/or memory components, for instance DRAMs (DRAM=Dynamic Random Access Memory and/or dynamic read/write memory) an internal voltage level used inside the component can differ from an external voltage level used outside the component.
In addition, several different internal voltage levels can be used—for instance between 1.5 V and 2.5 V for the core of a micro-controller and between 3 V and 5 V for the micro-controller input and output stages (ports).
A relatively low core voltage level has the advantage of allowing power losses inside the semiconductor component to be reduced, and for the elements of the micro-controller core to be manufactured with relatively small dimensions.
A relatively high port voltage level may be a requirement for allowing a semiconductor component to communicate with other components using corresponding external voltage levels.
The above external voltage level can be subject to relatively strong fluctuations and is therefore—in order to allow the component to be operated in a fault-free manner—usually converted by means of a voltage regulator to an internal voltage into an internal voltage (subject to relatively minor fluctuations and regulated to a particular constant reduced value).
To this end an external voltage regulator—independent of the relevant semiconductor component—can be used (for instance an external voltage regulator, which delivers the above core voltage, as well as the above port voltage).
In an alternative version, a corresponding—internal—voltage regulator (a so-called EVR (embedded voltage regulator)) can be provided on the semiconductor component itself, which generates the above core voltage from the above external voltage.
The provision of an internal voltage regulator has inter alia the disadvantage that a relatively large power loss, generated by the internal voltage regulator, has to be dissipated via the semiconductor component housing.
Conventional internal voltage regulators can for instance include a differential amplifier and a field effect transistor. The gate of the field effect transistor can be connected with an output of the differential amplifier and the source of the field effect transistors for instance with the external voltage supply.
A reference voltage—subject only to relatively minor fluctuations—is applied to the plus input of the differential amplifier. The voltage emitted at the drain of the field effect transistor can be back-connected directly with the minus input of the differential amplifier or with a voltage splitter inter-connected.
The differential amplifier regulates the voltage present at the gate connection of the field effect transistor in such a way that the (back-connected) drain voltage—and thereby the voltage emitted by the voltage regulator—remains constant and as high as the reference voltage, or for instance higher by a particular factor.
In a further alternative version for a voltage supply of a semiconductor component, an external power element, controlled by the semiconductor component, in particular a voltage tracking device can be used, into which an external voltage is fed, and which generates—under the control of the semiconductor component—a corresponding core voltage fed to the semiconductor component.
In the two latter versions (the EVR and the external power element), the core voltage can be controlled directly by the semiconductor component itself. Thereby the core voltage can be variably adjusted to the circumstances prevailing in each case and thereby the—total—energy consumption of the semiconductor component system can be reduced.
There are also versions available, in which a switch can be made between various voltage supply modes (supply by an EVR, or by an external power element, etc.) by applying a corresponding separate mode-switching control signal to an additional separate connection of the semiconductor component.